The video shown above is an example of interval expansion, an effect that can only be achieved through spectrogram resynthesis.

It consists in expanding the spacing in pitch between notes so that each interval doubles. Therefore, two notes one semitone apart become two semitones apart, which creates a melody that sounds different from the original melody. This is done here by setting analysis parameters so that only about 5 octaves of the original sound are analysed, then the frequency settings are changed so that these 5 octaves are stretched in pitch across 10 octaves.

It’s another example of some of the insane synthesis you can do with Photosounder and photo editing tools.

Details at the Photosounder blog.